Harkin wouldn’t have been primaried...he’s a liberal Dem icon, no dem would’ve primaried him. That’s what Republican Tea Partiers do to their rinos, not what Democrats do. Democrats circle the wagons on their liberal icons, they don’t primary them.
Perhaps you are thinking about the possibility that Harkin would have lost to a Republican. That wouldn’t have been in a primary, that would’ve been in a general election.
The point of my post was, I’m afraid that the Dems will run Tom Vilsak in Harkins’s place, and I’m afraid Vilsak, the former governor and current Obama AG secretary, would win.